This invention relates to a circuit module making up a drive circuit of a liquid crystal display device, etc.
For example, assuming that a 5.times.7-dot font is counted as one character in a liquid crystal display device, one semiconductor for driving the liquid crystal (hereinafter referred to as IC) having about 80 pins is required to display 16 characters.times.one line or eight characters.times.two lines. The drive circuit is made up of a circuit board on which ICs are connected, and is referred to as a circuit module.
FIG. 4 shows a conventional circuit module which consists of a plastic-molded IC 10 connected to a circuit board 11 whose double sides (face and reverse) are wired with wiring patterns. The reason why double sides of the circuit board 11 must be wired is that it enables an efficient wiring change and drawing for changing the pin order for smooth connection to a liquid crystal display element with respect to the pin assignments of the IC 10 and the actual electrode arrangement of the liquid crystal display element.
However, the circuit board 11 with double sides wired is high in production cost as compared with a circuit board with a single side wired, and results in increasing the cost of a circuit module. The cost of production of the circuit board 11 with double sides wired increases in proportion to its area.